Insufflation system

ABSTRACT

An aerosol generator is positioned adjacent to a patient as an attachment to a trocar. The trocar has an entry port for insufflation gas. Aerosol generated by a vibrating element is entrained in the insufflation gas and the mixture is delivered through the trocar. The aerosol may contain a medicament. The trocar may be a conventional trocar. Such trocars are typically used for a camera. The delivery of the aerosolized medicament can occur at the start of the procedure and be delivered in bolus. At the start of the procedure, the peritoneum is being inflated by means of the flow of insufflator gas. This gas flow will help to entrain the aerosolized medicament to the pneumoperitoneum regions. The surgeon can temporarily remove the camera from the trocar port to facilitate insertion and positioning of the aerosolizing unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. ProvisionalApplication Ser. No. 61/440,946 filed Feb. 9, 2011 and is acontinuation-in-part of U.S. patent application Ser. No. 12/853,538filed Aug. 10, 2010, which claims the benefit of U.S. ProvisionalApplication Ser. No. 61/232,512 filed Aug. 10, 2009. The disclosure ofeach of these applications is incorporated herein in its entirety byreference thereto.

BACKGROUND

Laparoscopic surgery, also called minimally or less invasive surgery(MIS or LIS) or keyhole surgery is a modern surgical technique in whichoperations in the body are performed through small incisions as comparedto the larger incisions needed in traditional surgical procedures. Gassuch as carbon dioxide is delivered, via an insufflator, into a bodycavity such as the abdomen leading to the formation of apneumoperitoneum, thereby providing sufficient space for the surgeon tooperate. The insufflator maintains the pneumoperitoneum and acts torenew the gas when leaks occur.

Gas, such as, for example, carbon dioxide, that is used for insufflationis both cold and dry and it is not surprising therefore those patientsundergoing laparoscopic procedures often suffer a significant drop incore body temperature, which can result in considerable post-surgicalpain and significant complications, such as cardiac stress,immunological and clotting problems, for the patient. By using standardthermo physical principles it has been shown that the major cause ofpatient heat loss is due to evaporation from the body acting to humidifythe large volumes of dry insufflated gas at ATPD (Ambient TemperaturePressure Dry) passing into the body which is at BTPS (Body TemperaturePressure Saturated). If such heat loss could be minimized,post-operative pain and the significant side effects suffered by thepatient could be considerably alleviated.

Various attempts have been made to condition insufflation gas byheating, humidifying, and/or filtering the gas. However, in general,known insufflation gas-conditioning systems suffer from one or moredisadvantages including complexity of construction involving expensivemonitoring devices, inaccurate control, and/or difficulties in usingthem in a controlled working environment.

Some systems employ heat moisture exchangers (HME). These operatedirectly in the flow path of the insufflation gas and are thereforeinherently susceptible to affecting pressure or flow, dependent upontheir level of saturation and condition. Other systems require manualintervention to respond to patients' needs by the adding of moisture.Other devices require the cumbersome procedure of passing gas over andthrough non-heated or heated liquid containers. Such devices present themajor drawback of impeding pressure measurement in the insufflationcavity.

Systems using conventional jet nebulizers or nebulization cathetersexhibit one or more of the following disadvantages: impaction of largerparticles; fogging in the body cavity thus reducing the surgeon'svisibility; and interference with insufflator settings increasingflow/pressure in the system.

The present invention is directed towards providing an insufflationmethod and apparatus.

Flow of aerosol through long lengths of tubing may lead to increasedrainout and loss of suspended aerosol delivered to the pneumoperitoneum.This impacts both effectiveness of the treatment and the time requiredto deliver any given medication volume.

Standard connections for inflow gas at a Trocar housing tend to be smalldiameter with sharp 90° changes in flow direction. This may lead toincreased rainout and loss of suspended aerosol delivered to thepneumoperitoneum.

Access to the control mechanism for the aerosol generator is generallyremote from the patient. This may inconvenience the surgeon whereimmediate changes in aerosol delivery are required during the course ofa procedure.

Delivery of aerosol into the pneumoperitoneum is generally completelydependent on the flow at insufflator. Where the insufflator is providinglow flow, aerosol may not be carried into the pneumoperitoneum.

Positioning the aerosol generating element on the tubing circuit betweenthe insufflator and the Trocar presents challenges such are location,need for supporting brackets, and potential to obscure displays onimportant equipment.

SUMMARY

In accordance with exemplary embodiments of the present invention anapparatus for use in procedures involving insufflation comprises:

-   -   an aerosol generator for aerosolizing a fluid; and    -   delivery means such as a delivery tube and/or a trocar for        delivery of the aerosol.

In some exemplary embodiments, the aerosol generator is mounted to thetrocar. The aerosol generator may be mountable to the trocar. Theaerosol generator may be releasably mounted to the trocar.

In some exemplary embodiments, the aerosol generator is integral withthe trocar.

The trocar may comprise an entry port for insufflation gas. Theapparatus may comprise means for entraining aerosol with an insufflationgas for delivery of the insufflation gas with entrained aerosol.

In some exemplary embodiments, the trocar comprises a housing having aproximal end to which the aerosol generator is mounted and a distal endthrough which aerosol is delivered, the trocar having a proximal entryport for insufflation gas, the apparatus comprising an aerosol deliverytub means extending from the aerosol generator into the trocar housing,the aerosol delivery tube having an aerosol outlet which is locateddistally with respect to the insufflation gas entry port of the trocar.

The aerosol outlet of the aerosol delivery tube may extend into thetrocar for a length which is at least 10%, at least 15%, or at least 20%of the length of the trocar.

Preferably there is a proximal seal between the trocar and the aerosoldelivery tube.

In some exemplary embodiments, the aerosol delivery tube comprises anentry port for receiving a flow of insufflation gas. The insufflationgas entry port of the aerosol delivery tube may be located proximally ofthe proximal end of the trocar.

The apparatus in accordance with some exemplary embodiments comprisesflow diverting means for delivery of insufflation gas to theinsufflation gas entry port of the trocar and/or to the insufflation gasentry port of the aerosol delivery tube.

In some other exemplary embodiments the aerosol delivery tube meanscomprises an inner tube and an outer tube which are spaced-apart todefine an insufflation gas flow path therebetween.

Preferably there is a distal seal between the outer tube and the trocar.

In some exemplary embodiments, the insufflation gas flow path extendsinto the aerosol delivery chamber for entraining insufflation gas withthe aerosol, the insufflation gas with entrained aerosol being deliveredthrough the inner tube and extending from the inner tube into the trocarat the distal end of the tube means.

The distal end of the outer tube may be located proximally with respectto the distal end of the inner tube to define an entry port forinsufflation gas.

In some exemplary embodiments, the aerosol generator is located at aproximal end of the trocar.

In some other exemplary embodiments, the aerosol generator is located ata distal end of the trocar. In this case the apparatus may comprise afirst delivery means for delivering insufflation gas to a locationadjacent to the aerosol generator.

The apparatus may comprise second delivery means for delivery of liquidto be aerosolized to the aerosol generator. The delivery means maycomprise a delivery tube extending from a liquid housing to the aerosolgenerator.

In some exemplary embodiments, the aerosol generator is mounted to anouter tube which extends through the trocar from the liquid housing. Adistal end of the outer tube may be located adjacent to a distal end ofthe trocar.

The aerosol generator may be located adjacent to a distal end of thetrocar.

In some exemplary embodiments, the apparatus comprises control means foroperation of the aerosol generator, the control means extending throughthe inner and outer tubes from a proximal end at the liquid housing to adistal end at the aerosol generator.

In some exemplary embodiments, the apparatus comprises an insufflatorfor generating an insufflation gas.

The apparatus may comprise a controller to control the operation of theaerosol generator. The controller may be remote from the trocar. Thecontroller may be mounted to the trocar. The controller may be mountableto the trocar. The controller may be releasably mounted to the trocar.

In some exemplary embodiments, the controller comprises a firstcontroller local to the trocar and a second controller remote from thetrocar.

The controller may be configured to control the flow rate of the fluidto be aerosolized.

In some exemplary embodiments, the controller is configured to deliverdifferent flow rates of aerosol at different stages of a surgicalprocedure.

In some exemplary embodiments, the controller is configured to deliverfull flow at the start and/or end of a procedure.

The controller may be configured to deliver reduced flow during aprocedure.

In some exemplary embodiments, the controller is set to deliver apre-set amount of aerosol into insufflation gas. The apparatus maycomprise means for varying the pre-set amount of aerosol. The means forvarying the pre-set amount of aerosol may comprise a user interface suchas a keypad or switch.

In some other exemplary embodiments, the controller is configured tocontrol operation of the aerosol generator responsive to theinsufflation gas. The controller may be configured to control operationof the aerosol generator responsive to the flow rate of the insufflationgas.

In some exemplary embodiments, the aerosol generator comprises avibratable member having a plurality of apertures extending between afirst surface and a second surface. The first surface may be adapted toreceive the fluid to be aerosolized. The aerosol generator may beconfigured to generate an aerosol at the second surface.

In some exemplary embodiments, the vibratable member is dome-shaped ingeometry. Alternatively, the vibratable member may comprise a stretchedflat shape.

In some exemplary embodiments, the vibratable member comprises apiezoelectric element.

In some exemplary embodiments, the apertures in the vibratable memberare sized to aerosolize the first fluid by ejecting droplets of thefirst fluid such that the majority of the droplets by mass have a sizeof less than 100 micrometers, less than 50 micrometers.

The apertures in the vibratable member may be sized to aerosolize thefirst fluid by ejecting droplets of the first fluid such that themajority of the droplets by mass have a size of less than 40micrometers.

The apertures in the vibratable member may be sized to aerosolize thefirst fluid by ejecting droplets of the first fluid such that themajority of the droplets by mass have a size of less than 30micrometers.

The apertures in the vibratable member may be sized to aerosolize thefirst fluid by ejecting droplets of the first fluid such that themajority of the droplets by mass have a size of less than 20micrometers. In some exemplary embodiments, a size range band is from 3to 15 micrometers.

In some exemplary embodiments, the controller is configured to controlthe pulse rate at a set frequency of vibration of the vibratable member.

The controller may be impedance matched to the aerosol generator.

In some exemplary embodiments, the apparatus comprises means todetermine whether the fluid is in contact with the aerosol generator.The determining means may be configured to determine at least oneelectrical characteristic of the aerosol generator. The determiningmeans may be configured to determine at least one electricalcharacteristic of the aerosol generator over a range of vibrationfrequencies.

In some exemplary embodiments, the determining means is configured tocompare the at least one electrical characteristic against a pre-definedset of data.

In accordance with exemplary embodiments of the present invention, amethod for carrying out a procedure involving insufflation comprises thesteps of:

-   -   providing an aerosol generator;    -   providing a trocar;

aerosolizing a fluid using the aerosol generator; and

-   -   delivering the aerosol from the trocar.

In accordance with exemplary embodiments of the present invention, amethod of introducing aerosol to a body cavity independent of the flowof insufflation gas is provided.

In some exemplary embodiments, the method comprises:

-   -   generating an insufflation gas; and    -   entraining the aerosol with the insufflation gas.

The method may comprise the step of controlling the aerosolization ofthe fluid.

The method may comprise delivering different flow rates of aerosol atdifferent stages of a surgical procedure. The method may comprisedelivering full flow at the start and/or end of a procedure. The methodmay comprise delivering reduced flow during a procedure. The methodcomprise delivering a pre-set amount of aerosol into insufflation gas.

In some exemplary embodiments, the method comprises the step ofdelivering the entrained fluid and insufflation gas into the body toinsufflate at least part of the body.

In some exemplary embodiments, the fluid is an aqueous solution.

In some exemplary embodiments, the aqueous solution is saline having asalt concentration of greater than 1 μM.

In some exemplary embodiments, the fluid contains a therapeutic and/orprophylactic agent.

The agent may be one or more selected from the group comprising ananalgestic, an anti-inflammatory, an anti-infective, an anaesthetic, ananticancer chemotherapy agent, and an anti-adhesion agent.

In some exemplary embodiments, the procedure is a laparascopicprocedure.

In accordance with exemplary embodiments of the present invention, anapparatus for use in procedures involving insufflation comprises:

-   -   an aerosol generator for aerosolizing a fluid,    -   a trocar for delivery of the aerosol, the trocar comprising a        housing to which the aerosol generator is mounted, the trocar        having a proximal entry part for insufflation gas and a distal        end through which aerosol is delivered,    -   the apparatus comprising an aerosol delivery tube extending from        the aerosol generator into the trocar housing, the aerosol        delivery tube having an aerosol outlet which is located distally        with respect to the insufflation gas entry port of the trocar.

In some exemplary embodiments, a proximal end of the aerosol deliverytube is located adjacent to the aerosol generator.

In some exemplary embodiments, the apparatus is adapted to directinsufflation gas from the trocar insufflation gas entry port to aproximal end of the aerosol delivery tube for entraining the aerosol inthe insufflation gas and delivery of the insufflation gas and entrainedaerosol through the trocar.

A gap may be provided between the aerosol delivery tube and the aerosolgenerator for delivery of insufflation gas into the aerosol deliverytube at the proximal end thereof.

In an exemplary case the gap is defined by an angled cut at the proximalend of the aerosol delivery tube. The angle cut may be less than 20°,less than 15°, less than 10°. In one embodiment the angle cut isapproximately 5°.

There may be a proximal seal between the trocar and the aerosol deliverytube.

The aerosol delivery tube means may comprise an inner tube and an outertube which are spaced-apart to define an insufflation gas flow paththerebetween. There may be a distal seal between the outer tube and thetrocar.

The trocar systems of the present invention may be adapted toaccommodate two or more aerosol generators. Such systems with more thanone aerosol generator increases nebulizer output and reduces the timerequired to deliver a required amount of aerosol.

In some exemplary embodiments, there is a seal between the distal end ofa trocar insert the trocar to prevent insufflation gas from passingbetween the outer wall of the insert and the inner wall of the trocar.The seal may comprise a bulbous region at the distal end of the insertwhich is an interference fit in the shaft of the trocar. Thisarrangement facilitates ease of insertion and removal of the trocarinsert whilst maintaining a seal when the insert is in place in thetrocar.

There may be any desired number of aerosol generators.

In some exemplary embodiments, a trocar insert has a shortened length Lwhich is sufficient to create a seal between the trocar insert and theinner surface of the trocar. Typically the length L is between 30 mm and65 mm. By reducing the distance the distance to be travelled by theaerosol within the narrow trocar insert the quantity of aerosol exitingthe trocar is increased.

In some exemplary embodiments, an inner tube of a trocar insert isextended to a position close to the underside of an aerosol generator.This has the benefit of channelling the flow of generated aerosol fordelivery to a patient. This feature may be used with any length oftrocar insert. Many different arrangements are possible. There may be asmall gap, a tapered interface, an interface with castellations, asingle gas inlet slit, and/or dual offset slits to promote vortexformation.

In some exemplary embodiments, an aerosol insert has a modifiedinterface between a proximal end of an inner tube of the insert and anaerosol generator. In some exemplary embodiments, the inner tube comesinto contact with the aerosol generator. The inner tube may have aninlet for insufflation gas which is spaced below the proximal end of theinner tube. This modifies the aerosol flow dynamics for improved aerosoldelivery efficiency.

A liquid reservoir for the aerosol generator may be modified tofacilitate efficient nebulization through a wide range of angles oforientation such as would be encountered in use during laparoscopicsurgery. In some exemplary embodiments, a reservoir is tapered. Thereservoir may be fitted with a removable plug. The plug may, forexample, be of silicon.

In accordance with exemplary embodiments of the present invention, atrocar having an aerosol generator includes a valve such as a flap valveto facilitate the insertion of an instrument such as a trocar blade orobdurator. As the instrument is inserted, the flap valve moves toprotect the aerosol generator. When the instrument is not present theflap returns to a rest position and assists in directing the flow ofaerosol generated by the aerosol generator down the shaft of the trocar.

Further features and aspects of example embodiments of the presentinvention are described in more detail below with reference to theappended Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an apparatus in accordance with thepresent invention for use in a procedure involving insufflation of abody cavity, such as laparoscopic surgery.

FIG. 2 is a perspective view of another apparatus in accordance with thepresent invention.

FIG. 3 is a perspective view of another apparatus in accordance with thepresent invention.

FIG. 4 is a perspective view of another apparatus in accordance with thepresent invention.

FIG. 5 is a perspective view of the apparatus of FIG. 4 with a leadconnected.

FIG. 6 is an exploded view of another apparatus in accordance with thepresent invention.

FIG. 7 is a perspective view of the apparatus of FIG. 6 assembled.

FIG. 8 is a perspective view of the apparatus of FIGS. 6 and 7 mountedto a trocar.

FIG. 9 is a cross sectional view of the apparatus of FIG. 8.

FIG. 10 is a cross sectional view of another aerosol generator systemmounted to a trocar.

FIG. 11 is an enlarged view of part of the apparatus of FIG. 10.

FIG. 12 is a cross sectional view of a further aerosol generator systemmounted to a trocar.

FIG. 13 is an enlarged view of part of the apparatus of FIG. 12.

FIG. 14 is a cross sectional view of another aerosol generator systemmounted to a trocar.

FIG. 15 is an enlarged view of one part of the apparatus of FIG. 14.

FIG. 16 is an enlarged view of another part of the apparatus of FIG. 14.

FIG. 17 is a cross sectional view of an alternative seal.

FIG. 18 is a cross sectional view of a further aerosol generator systemmounted to a trocar.

FIG. 19 is an enlarged view of one part of the apparatus of FIG. 18.

FIG. 20 is an enlarged view of another part of the apparatus of FIG. 18.

FIG. 21 is a schematic illustration of a part of an apparatus inaccordance with the present invention.

FIG. 22 is a schematic illustration of a part of the apparatus of FIG.21.

FIG. 23 is an exploded isometric view of an aerosol generator used inthe present invention.

FIG. 24 is a cross-sectional view of the assembled aerosol generator ofFIG. 23.

FIG. 25 is a perspective view of a controller housing used in theapparatus of the present invention.

FIGS. 26 and 27 are graphs of DC voltage versus time and AC voltageversus time respectively to achieve a 100% aerosol output.

FIGS. 28 and 29 are graphs of DC voltage versus time and AC voltageversus time respectively to achieve a 50% aerosol output—FIG. 28illustrates the waveform output from a microprocessor to a drive circuitand FIG. 29 illustrates the waveform output from a drive circuit to anebulizer.

FIGS. 30 and 31 are graphs of DC voltage versus time and AC voltageversus time respectively to achieve a 25% aerosol output—FIG. 30illustrates the waveform output from a microprocessor to a drive circuitand FIG. 31 illustrates the waveform output from a drive circuit to anebulizer.

FIG. 32 is a graph of AC voltage versus time; and illustrates an outputwaveform from a drive circuit to a nebulizer.

FIG. 33 is a graph of frequency versus current for another apparatus inaccordance with the present invention.

FIG. 34 is a perspective view of another apparatus in accordance withthe present invention.

FIG. 35 is an elevational view of portion of another apparatus inaccordance with the present invention for use in a procedure involvinginsufflation of a body cavity, such as laparoscopic surgery.

FIG. 36 is a top plan view of the apparatus of FIG. 35.

FIG. 37 is a plan view of another apparatus in accordance with thepresent invention.

FIG. 38 is an elevational view of another apparatus in accordance withthe present invention.

FIG. 39 is an elevational view of another apparatus in accordance withthe present invention.

FIG. 39( a) is an enlarged view of a detail of FIG. 39.

FIG. 40 is an enlarged view of detail A of the apparatus of FIG. 39.

FIG. 41 is an elevational view of another apparatus in accordance withthe present invention.

FIG. 42 is an elevational view of a further apparatus in accordance withthe present invention.

FIG. 42( a) is an enlarged plan view of a detail of FIG. 42.

FIG. 43 is an elevational view of another apparatus in accordance withthe present invention.

FIG. 43( a) is an enlarged plan view of a detail of FIG. 43.

FIG. 44 is an elevational view of a further apparatus in accordance withthe present invention.

FIG. 45 is a plan view of a detail of FIG. 44 illustrating a gas flowpath.

FIG. 46 is an elevational view of another apparatus in accordance withthe present invention.

FIG. 47 is an elevational view of an apparatus in accordance with thepresent invention.

FIG. 48 is an elevational view of a further apparatus in accordance withthe present invention.

DETAILED DESCRIPTION

Referring to FIG. 1 there is illustrated an apparatus in accordance withthe present invention for use in insufflation of a body cavity. One suchapplication is laparoscopic surgery. The device is also suitable for usein any situation involving insufflation of a body cavity such as inarthroscopies, pleural cavity insufflation (for example duringthoracoscopy), retroperitoneal insufflations (for exampleretroperitoneoscopy), during hernia repair, during mediastinoscopy andany other such procedure involving insufflation.

The apparatus comprises a reservoir 1 for storing an aqueous solution,an aerosol generator 2 for aerosolizing the solution, and a controller 3for controlling operation of the aerosol generator 2. In the presentinvention aerosolized aqueous solution is entrained with insufflationgas. The gas is any suitable insufflation gas such as carbon dioxide.Other examples of suitable insufflation gases are nitrogen, helium, andxenon.

The insufflation gas is delivered into an insufflation gas tubing 15 byan insufflator 12. The insufflator 12 may be of any suitable type suchas those available from Karl Storz, Olympus, and Stryker. Theinsufflator 12 has an outlet 20 through which insufflation gas isdelivered. A bacterial filter 21 may be provided within the insufflatoror, as illustrated, downstream of the insufflator outlet 20.

Sterile water may be used. In the case of an aqueous solution, anysuitable solution may be used. Solutions with a salt concentration inthe range 1 μM (micro molar) to 154 mM (milli molar) (0.9% saline) areoptimum as they cover the majority of medical applications. In addition,such saline concentrations can be readily nebulized using theaerosolization technology used in the present invention.

Liquid, saline or water for humidifying purposes only and/or medicament,can be delivered into the nebulizer reservoir through the opening in thetop of the nebulizer that is appropriately sized to receive standardnebules or alternatively may be applied by syringe or other deliverymeans. In another exemplary embodiment it would be possible to supplythe nebulizer pre-loaded with medicament avoiding the requirement toseparately add medicament to the system.

Aqueous solution may be stored in the reservoir 1 container of thenebulizer.

The apparatus comprises an aerosol supply conduit 34 for delivering theaerosol from the aerosol generator 2 into the insufflation gas conduit15 to entrain the aerosol with the insufflation gas, passing through thegas insufflation conduit 15. The entrained aerosol/insufflation gasmixture passes out of the connector 30 through the outlet 32 and isdelivered to the body cavity along a line 60 to a trocar 9.

The aerosol supply conduit 34 and the insufflation gas conduit meet at ajunction. Referring particularly to FIGS. 23 and 24, in the assembledapparatus the aerosol supply conduit 34 may be releasably mounted to aneck 36 of the aerosol generator housing by means of a push-fitarrangement. This enables the conduit 34 to be easily dismounted fromthe aerosol generator housing 36, for example for cleaning The neck 36at least partially lines the interior of the aerosol supply conduit 34.

The nebulizer (or aerosol generator), has a vibratable member which isvibrated at ultrasonic frequencies to produce liquid droplets. Somespecific, non-limiting examples of technologies for producing fineliquid droplets is by supplying liquid to an aperture plate having aplurality of tapered apertures extending between a first surface and asecond surface thereof and vibrating the aperture plate to eject liquiddroplets through the apertures. Such technologies are describedgenerally in U.S. Pat. No. 5,164,740, U.S. Pat. No. 5,938,117, U.S. Pat.No. 5,586,550, U.S. Pat. No. 5,758,637, U.S. Pat. No. 6,014,970, U.S.Pat. No. 6,085,740, and U.S. Pat. Application Publication No.2005/021766A, the complete disclosures of which are incorporated hereinby reference. However, it should be appreciated that the presentinvention is not limited for use only with such devices.

Various methods of controlling the operation of such nebulizers oraerosol generators are described in U.S. Pat. No. 6,540,154, U.S. Pat.No. 6,845,770, U.S. Pat. No. 5,938,117, and U.S. Pat. No. 6,546,927, thecomplete disclosures of which are incorporated herein by reference.

In use, the liquid to be aerosolized is received at the first surface,and the aerosol generator 2 generates the aerosolized first fluid at thesecond surface by ejecting droplets of the first fluid upon vibration ofthe vibratable member. The apertures in the vibratable member are sizedto aerosolize the liquid by ejecting droplets of the liquid such thatthe majority of the droplets by mass have a size of less than 5micrometers. The vibratable member 40 could be non-planar, and may bedome-shaped in geometry.

Referring particularly to FIGS. 23 and 24, in an exemplary case theaerosol generator 2 comprises a vibratable member 40, a piezoelectricelement 41 and a washer 42, which are sealed within a silicone overmold43 and secured in place within the housing 36 using a retaining ring 44.The vibratable member 40 has a plurality of tapered apertures extendingbetween a first surface and a second surface thereof.

The first surface of the vibratable member 40, which in use facesupwardly, receives the liquid medicament from the reservoir 1 and theaerosolized medicament, is generated at the second surface of thevibratable member 40 by ejecting droplets of medicament upon vibrationof the member 40. In use, the second surface faces downwardly. In anexemplary case, the apertures in the vibratable member 40 may be sizedto produce an aerosol in which the majority of the droplets by weighthave a size of less than 5 micrometers.

The complete nebulizer may be supplied in sterile form, which is asignificant advantage for a surgical device.

Referring particularly to FIG. 22, the controller 3 controls operationof and provides a power supply to the aerosol generator 2. The aerosolgenerator has a housing which defines the reservoir 1. The housing has asignal interface port 38 fixed to the lower portion of the reservoir 1to receive a control signal from the controller 3. The controller 3 maybe connected to the signal interface port 38 by means of a control lead39 which has a docking member 50 for mating with the port 38. A controlsignal and power may be passed from the controller 3 through the lead 39and the port 38 to the aerosol generator 2 to control the operation ofthe aerosol generator 2 and to supply power to the aerosol generator 2respectively.

The power source for the controller 3 may be an on-board power source,such as a rechargeable battery, or a remote power source, such as amains power source, or an insufflator power source. When the remotepower source is an AC mains power source, an AC-DC converter may beconnected between the AC power source and the controller 3. A powerconnection lead may be provided to connect a power socket of thecontroller 3 with the remote power source.

Referring particularly to FIG. 25, the controller 3 has a housing and auser interface to selectively control operation of the aerosol generator2. Preferably the user interface is provided on the housing which, inuse, is located remote from the aerosol generator housing. The userinterface may be in the form of, for example, an on-off button. In someembodiments a button may be used to select pre-set values for simplicityof use. In some embodiments a dial mechanism may be used to select froma range of values from 0-100%.

Status indication means are also provided on the housing to indicate theoperational state of the aerosol generator 2. For example, the statusindication means may be in the form of two visible LEDs, with one LEDbeing used to indicate power and the other LED being used to indicateaerosol delivery. Alternatively, one LED may be used to indicate anoperational state of the aerosol generator 2, and the other LED may beused to indicate a rest state of the aerosol generator. 2.

A fault indicator may also be provided in the form of an LED on thehousing. A battery charge indicator in the form of an LED may beprovided at the side of the housing.

The controller 3 may be activated to supply power and a control signalto the aerosol generator 2, which causes the piezoelectric element 41 tovibrate the non-planar member 40. This vibration of the non-planarmember 40, causes the aqueous solution at the top surface of the member40 to pass through the apertures to the lower surface where the aqueoussolution is aerosolized by the ejection of small droplets of solution.

Referring particularly to FIGS. 23 and 24, the aerosol passes from theaerosol generator 2 into the neck 36 of the aerosol generator housing,which is mounted within the aerosol supply conduit 34. The aerosol isentrained in the insufflation gas conduit with gas. The entrainedmixture of the aerosol and the insufflation gas then passes via aninsufflator line 60 to a trocar 9, for example into the abdomen of thepatient.

In use during laparoscopic surgery, the flow of the insufflation gasinto the abdomen of a patient is commenced to insufflate the abdomen.The controller 3 commences operation of the aerosol generator 2 toaerosolize the aqueous solution. The aerosolized aqueous solution isentrained with the insufflation gas, and delivered through the trocar 9into the abdomen of the patient to insufflate at least part of theabdomen.

In the event of alteration of the fluid flow rate of the insufflationgas a flow rate sensor/meter may determine the alteration, and thecontroller 3 alters the pulse rate of the vibratable member of thenebulizer accordingly.

The controller 3 may be configured to control operation of the aerosolgenerator 2, responsive to the fluid flow rate of the insufflation gasand/or also independent of the fluid flow rate of the insufflation gas.

In an exemplary case, the controller 3 is configured to controloperation of the aerosol generator 2 by controlling the pulse rate at aset frequency of vibration of the vibratable member, and thuscontrolling the fluid flow rate of the aqueous solutions.

The controller 3 may comprise a microprocessor 4, a boost circuit 5, anda drive circuit 6. FIG. 21 illustrates the microprocessor 4, the boostcircuit 5, the drive circuit 6 comprising impedance matching components(inductor), the nebulizer 2, and the aerosol. The inductor impedance ismatched to the impedance of the piezoelectric element of the aerosolgenerator 2. The microprocessor 4 generates a square waveform of 128 KHzwhich is sent to the drive circuit 6. The boost circuit 5 generates a12V DC voltage required by the drive circuit 6 from an input of either a4.5V battery or a 9V AC/DC adapter. The circuit is matched to theimpedance of the piezo ceramic element to ensure enhanced energytransfer. A drive frequency of 128 KHz is generated to drive thenebulizer at close to its resonant frequency so that enough amplitude isgenerated to break off droplets and produce the aerosol. If thisfrequency is chopped at a lower frequency such that aerosol is generatedfor a short time and then stopped for a short time, this gives goodcontrol of the nebulizer's flow rate. This lower frequency is called thepulse rate.

The drive frequency may be started and stopped as required using themicroprocessor 4. This allows for control of flow rate by driving thenebulizer 2 for any required pulse rate. The microprocessor 4 maycontrol the on and off times to an accuracy of milliseconds.

The nebulizer 2 may be calibrated at a certain pulse rate by measuringhow long it takes to deliver a know quantity of solution. There is alinear relationship between the pulse rate and the nebulizer flow rate.This allows for accurate control over the delivery rate of the aqueoussolution.

The nebulizer drive circuit includes or consists of the electroniccomponents designed to generate output sine waveform of approximately100V AC which is fed to nebulizer 2 causing aerosol to be generated. Thenebulizer drive circuit 6 uses inputs from microprocessor 4 and boostcircuit 5 to achieve its output. The circuit is matched to the impedanceof the piezo ceramic element to ensure good energy transfer.

The aerosol generator 2 may be configured to operate in a variety ofdifferent modes, such as continuous, and/or phasic, and/or optimised.

For example, referring to FIG. 26, a 5V DC square waveform output fromthe microprocessor 4 to the drive circuit 6. FIG. 27 shows a low power,˜100V AC sine waveform output from drive circuit 6 to nebulizer 2 isillustrated. Both waveforms have a period p of 7.8 μS giving them afrequency of 1/7.8 μs which is approximately 128 KHz. Both waveforms arecontinuous without any pulsing. The aerosol generator may be operated inthis mode to achieve 100% aerosol output.

Referring to FIG. 28 in another example, there being illustrated a 5V DCsquare waveform output from the microprocessor 4 to the drive circuit 6.FIG. 29 shows a low power, ˜100V AC sine waveform output from the drivecircuit 6 to the nebulizer 2. Both waveforms have a period p of 7.8 μSgiving them a frequency of 1.78 μs which is approximately 128 KHz. Inboth cases the wavefoms are chopped (stopped/OFF) for a period of timex. In this case the off time x is equal to the on time x. The aerosolgenerator may be operated in this mode to achieve 50% aerosol output.

In another exemplary case, referring to FIG. 30 there is illustrated a5V DC square waveform output from microprocessor 4 to drive circuit 6.FIG. 31 shows a low power, ˜100V AC sine waveform output from the drivecircuit 6 to the nebulizer 2. Both waveforms have a period p of 7.8 μSgiving them a frequency of 1/7.8 μs which is approximately 128 KHz. Inboth cases the wavefoms are chopped (stopped/OFF) for a period of timex. In this case the off time is 3x while the on time is x. The aerosolgenerator may be operated in this mode to achieve 25% aerosol output.

Referring to FIG. 32, in an exemplary application pulsing is achieved byspecifying an on-time and off-time for the vibration of the apertureplate. If the on-time is set to 200 vibrations and off-time is set to200 vibrations, the pulse rate is 50% (½ on ½ off). This means that theflow rate is half of that of a fully driven aperture plate. Any numberof vibrations can be specified but to achieve a linear relationshipbetween flow rate and pulse rate a minimum number of on-time vibrationsis specified since it takes a finite amount of time for the apertureplate to reach its maximum amplitude of vibrations.

The drive frequency can be started and stopped as required by themicroprocessor; this allows control of flow rate by driving thenebulizer for any required pulse rate. The microprocessor can controlthe on and off times with an accuracy of microseconds.

A nebulizer can be calibrated at a certain pulse rate by measuring howlong it takes to deliver a known quantity of solution. There is a linearrelationship between the pulse rate and that nebulizer's flow rate. Thisallows accurate control of the rate of delivery of the aerosolizedaqueous solution. The ability to calibrate each nebulizer ensures thatany inherent variation in output rate between each nebulizer can beeliminated. The output from each nebulizer when in-line in theinsufflator circuit will be equivalent to a second nebulizer althoughthe inherent flow rates of the two nebulizers are different. Forexample, to achieve a standard output of 0.044 ml/min at 1 L/min fromtwo nebulizers, one with an inherent output of 0.088 ml/min and a secondwith an inherent output of 0.176 ml/min, the first nebulizer iscontrolled with a 50:50 on:off pulse rate, with the second set to a25:75 on-off pulse rate so that both nebulizers give a 0.044 ml/minoutput. This feature ensures that the nebulizers when located in theinsufflation circuit have the potential to provide exactly the same rateof aerosol output as each other. This is possible because the amount ofhumidity a gas can hold is a known constant dependent on controllablefactors.

The pulse rate may be lowered so that the velocity of the emergingaerosol is much reduced so that impaction rain-out is reduced.

Detection of when the aperture plate is dry can be achieved by using thefact that a dry aperture plate has a well defined resonant frequency. Ifthe drive frequency is swept from 120 kHz to 145 kHz and the current ismeasured then if a minimum current is detected less than a set value,the aperture plate must have gone dry. A wet aperture plate has noresonant frequency. The apparatus of the present invention may beconfigured to determine whether there is any of the first fluid incontact with the aerosol generator 2. By determining an electricalcharacteristic of the aerosol generator 2, for example the currentflowing through the aerosol generator 2, over a range of vibrationfrequencies, and comparing this electrical characteristic against apre-defined set of data, it is possible to determine whether the aerosolgenerator 2 has any solution in contact with the aerosol generator 2.FIG. 33 illustrates a curve 80 of frequency versus current when there issome of the solution in contact with the aerosol generator 2, andillustrates a curve 90 of frequency versus current when there is none ofthe solution in contact with the aerosol generator 2. FIG. 33illustrates the wet aperture plate curve 80 and the dry aperture platecurve 90.

Humidity may be generated via the aerosolization of any aqueoussolution. Relative humidity in the 50-100% range would be optimum. Thecontrol module can generate a nebulizer output of any defined relativehumidity percentage based on the insufflator flow. These solutionsinclude any aqueous drug solution. Solutions with salt concentrations inthe range 1 μM-154 mM would be optimum.

The use of the nebulizer to humidify the insufflation gas prior toentering the body will eliminate the need for the body to humidify thegas once it is inside the body, thereby minimizing body heat loss byinternal evaporation.

The control in nebulizer output allows proportional delivery of therequired amount of humidity according to the amount of insufflation gasentering the body. In addition, this control of aerosolization rate willprevent overloading of the insufflation gas with aerosol, which wouldobscure the surgeons view.

Exemplary embodiments of the present invention provide a system that candeliver different flow rates at different stages of the surgicalprocedure. Examples of such different flow rates include:

-   -   (i) delivering at 100% at the start of the procedure (Bolus);    -   (ii) delivering at a much lower rate say 5% during the procedure        itself (Lower flow rate avoid fogging);    -   (iii) delivering at 100% at the end of the procedure (Bolus);    -   (iv) any combination of the above sequencing with variable %        values.

In an exemplary case, the controller which controls the operation of theaerosol generator is pre-set to deliver a set amount of aerosol into theinsufflation gas. For example, the controller may be set to deliver anamount of 5% into a flow of 1 liter per minute of insufflation gas toavoid fogging. The controller may be pre-set in the factory to operatein this manner. Alternatively, there may be a user interface such as aswitch, or keypad which may be used to change the setting. In thesearrangements, control responsive to an insufflation gas flow sensor isnot essential.

In addition to acting as a humidifying agent, the nebulizer may also actto deliver any agent presented in an aqueous drug solution. The systemmay facilitate delivery of, for example, pain-relief medications,anti-infectives, anti-inflammatory, and/or chemotherapy agents inaerosol form to the body cavity. These therapeutic agents may also actas humidifying substances in their own right.

The nebulized liquid entrained in the insufflation gas may contain anydesired therapeutic and/or prophylactic agent. Such an agent may forexample be one or more of an analgesic, an anti-inflammatory, ananaesthetic, an anti-infective such as an antibiotic, an anti-cancerchemotherapy agent, and/or any agent which interferes with processesthat result in the adhesion function.

Typical local anaesthetics are, for example, Ropivacaine, Bupivacaine,and Lidocaine.

Typical anti-infectives include: antibiotics such as an aminoglycoside,a tetracycline, a fluroquinolone; and anti-microbials such as acephalosporin; and anti-fungals.

Anti-inflammatories may be of the steroidal or non-steroidal type.

Anti-cancer chemotherapy agents may be alkylating agents,antimetabolites anthracyclines, plant alkaloids, topoisomeraseinhibitors, nitrosoureas, mitotic inhibitors, monoclonal antibodies,tyrosine kinase inhibitors, hormone therapies including corticosteroids,cancer vaccines, anti-estrogens, aromatase inhibitors, anti-androgens,anti-angiogenic agents, and other antitumour agents.

The agent which interferes with the adhesion function may be any ofthose outlined in PCT Application Publication No. WO2005/092264A, theentire contents of which are incorporated herein by reference. Inparticular, the agent may be a crystalloid, hyaluronic acid,polyehtyleneglycol, Tranilast (N-(3¹,4¹-dimethoxycinnamoyl) anthranilicacid) or a Neurokinin 1 receptor (NK-1R) agonist, such as Aprepitant.

Typical analgesics include aspirin, acetaminophen, ibuprofen, naproxen,a Cox-2 inhibitor such as celecoxib, morphine, oxycodone, andhydrocodone.

To aid drug delivery at least some of the surfaces which come intocontact with the drug may be coated. Any suitable coating may be usedsuch as those with hydrophobic properties will cause the drug to repelfrom the surface and assist in maintaining the aerosol in motion throughto the patient. PTFE based coatings such as Teflon are examples ofappropriate coatings.

Alternatively or additionally, an appropriate electrostatic charge maybe used to assist in maintaining the aerosol in motion. If a drug has aparticular charge, adding a similar charge to a surface with which theycome into contact will cause the aerosolized drug to repel from thesurface, thus keeping the drug in the aerosol path to the patient.

These approaches may be applied to any aerosolized drug delivery systemincluding but not limited to insufflation systems of the type describedherein. It may be applied to nebulization/aerosolization systems ingeneral for home and/or hospital use.

Exemplary systems of the present invention may be used for precisecontrolled delivery of drug and/or humidity during insufflation. Noheating is required. Consequently there is no risk of damage to drugsdue to heating. The system may be used to provide precise control overaerosol output, where such control may be exercised, for example, byutilizing pulse rate control. The system may be used for targeteddelivery of a range of drugs, thereby reducing systemic side effects. Inaddition the system provides alleviation of post-surgical painexperienced by the patient.

Referring to FIGS. 2 and 3 an aerosol generating element 2 is positionedadjacent to the patient as an attachment to the trocar tool/instrument 9with a remote located drive controller 3, connected via a lead 16 to theaerosol generating element 2.

Referring to FIGS. 4 and 5, in another arrangement the aerosolgenerating element is integrated into a trocar tool/instrument 100 andthe controller for the aerosol generator is also fully integrated intothe trocar.

Referring to FIGS. 6 to 9, the aerosol generating device 2 may beinserted into an entry port 110 of a surgery trocar 111. The trocar 111may be a conventional trocar with an entry port having a diameter ofcirca 10 mm. Such trocars are typically one used for a camera. A size ofabout 10 mm facilitates maximum inflow of aerosol.

The delivery of the aerosolized medicament can occur at the start of theprocedure and be delivered in bolus. At the start of the procedure, theperitoneum is being inflated by means of the flow of insufflator gas.This gas flow will help to entrain the aerosolized medicament to thepneumoperitoneum regions. The surgeon can temporarily remove the camerafrom the trocar port to facilitate insertion and positioning of theaerosolizing unit.

The medicament can also be aerosolized when the peritoneum is inflated,by assisting the flow of aerosol by generating a larger pressure dropacross the peritoneum cavity. This can be accomplished by creating anartificial leak or vent of CO2 from the cavity. This could be designedinto the spigot of the aersolising device that fits into the trocar port110.

The aerosol may be generated directly above the trocar entry point intothe pneumoperitoneum and in one embodiment can be powered via a cable 16attached to the separate controller unit 3. In an exemplary caseillustrated in FIG. 2, the insufflator gas from the insufflator 12enters the trocar 9 from the line 15 via a separate port 17 andgenerated aerosol is carried into the pneumoperitoneum by entrainment inthe gas flow and through the effects of gravity and diffusion. Thecontroller 3 may be located near to the trocar location or at someremote location as allowed by the cable length 16 and the surgeon'sdesired ergonomical preferences.

In another exemplary case illustrated in FIG. 3, the trocar 9 mayprovide a port 13 for the aerosol generator 2 only with no provision forinsufflator gas inflow. In this embodiment, the generated aerosol iscarried into the pneumoperitoneum through the effects of gravity,diffusion, and the residual velocity of aerosol after exiting theaerosol generator. The controller 3 may be located near to the trocarlocation or at some remote location as allowed by the cable length 16.

In the device illustrated in FIGS. 4 and 5, both the aerosol generator 2and control 3 functionality are integrated into one self contained unitand placed in the trocar housing 100. The aerosol is generated directlyabove the trocar entry point into the pneumoperitoneum. The insufflatorgas enters the trocar via a separate port 17 and generated aerosol iscarried into the pneumoperitoneum by entrainment in the gas flow andthrough the effects of gravity and diffusion. Control functionality isavailable directly at the trocar body via buttons, indicator lights,displays, or other user interfaces 120. The integrated device may beoperated via internal battery power or from an external power source viaa power supply cable. The device may also have a charger port 122 forcharging of an internal battery via an external power supply cable 121.Therefore it is possible that there are no attached or trailing cableleads on the aerosol generating device during the surgical proceduregreatly aiding the surgeon's ease of use of the equipment andcontributing to the whole aesthetics of the equipment set up.

The integrated trocar may have no provision for insufflator gas inflow.The control functionality may be driven by a battery built into thetrocar nebulizer body. In this embodiment, the generated aerosol iscarried into the pneumoperitoneum through the effects of gravity,diffusion and the residual velocity of aerosol after exiting the aerosolgenerator.

The nebulizer on the trocar may be provided with a particulargeometrical configuration to receive mating nebule geometry. This willfacilitate the aerosolization of this drug only within the predesignednebule and no other drug. This would allow for targeted delivery ofsmall volumes of high concentration drug to the aperture plate, thusminimizing residual drug wastage.

Referring to FIGS. 6 to 9 an aerosol generator trocar insert 130delivers aerosol through the trocar with no provision for insufflatorgas inflow. The trocar insert 130 is of a length that will allow aerosolgenerated to be delivered beyond any trocar valve. In this embodiment,the generated aerosol is carried into the pneumoperitoneum through theeffects of gravity, diffusion and the residual velocity of aerosol afterexiting the aerosol generator. The controller 3 may be located near tothe trocar location or at some remote location as allowed by the cablelength.

The aerosol generator and control functionality may be integrated intothe aerosol generator trocar insert. The trocar insert will be of alength that will allow aerosol generated to be delivered beyond anytrocar valve. In this case the aerosol is generated directly above thetrocar entry point into the pneumoperitoneum. The insufflator gas entersthe trocar via a separate port 17 and generated aerosol is carried intothe pneumoperitoneum by entrainment in the gas flow and through theeffects of gravity and diffusion. Control functionality may be availabledirectly at the trocar body via buttons, indicator lights, displays orother user interfaces. The integrated device may be operated viainternal battery power or from an external power source via a powersupply cable. The device may also have provision for charging of theinternal battery via the external power supply cable.

Alternatively, the aerosol generator trocar insert may have no provisionfor insufflator gas inflow. In a further embodiment, the controlfunctionality may be driven by a battery built into the trocar insertaerosol generator body. In this embodiment, the generated aerosol iscarried into the pneumoperitoneum through the effects of gravity,diffusion and the residual velocity of aerosol after exiting the aerosolgenerator.

Referring to FIGS. 10 and 11 there is illustrated another aerosolgenerator system 200 mounted to a trocar 201 having a proximal trocarseal 202. In this case the trocar 201 has an inlet 203 for insufflationgas. The aerosol generator system 200 comprises a vibrating mesh/plate205 and a reservoir 204 for fluid to be aerosolized. Aerosol 207 passesdown through a delivery tube 206 and is entrained with insufflation gas208. The mixture 209 is then delivered through the trocar 201 into apatient's abdomen. The trocar comprises a housing having a proximal endto which the aerosol generator is mounted and a distal end through whichaerosol is delivered. The trocar has a proximal entry port 203 forinsufflation gas. The apparatus comprises an aerosol delivery tube meansextending from the aerosol generator 200 into the trocar housing. Theaerosol delivery tube has an aerosol outlet 300 which is locateddistally with respect to the insufflation gas entry port 203 of thetrocar. In this case the aerosol outlet 300 of the aerosol delivery tube206 extends into the trocar for a length which is at least 10%, at least15%, or at least 20% of the length of the trocar. There is a proximalseal 202 between the trocar and the aerosol delivery tube 206.

The embodiment of FIGS. 10 and 11 has the advantage of ease ofmanufacture and use. It does not require auxiliary seals and does notrequire elaborate fluid pathways.

Referring to FIGS. 12 and 13, there is illustrated another aerosolgenerator system and trocar which is similar to that described withreference to FIGS. 10 and 11 and like parts are assigned the samereference numerals. In this case an inlet supply line 250 forinsufflation gas is split into a first leg 251 for delivery to an inlet252 below the vibrating plate/mesh 205 and a second leg 253 for deliveryto the trocar inlet 203. There is a valve 254 on the aerosol generatorsupply line 251 and valves 255, 256 on the trocar supply line 253. Inuse, the valve 255 is closed and the valve 254 is opened when it isdesired to deliver insufflation gas to the aerosol generator. Thegenerated aerosol 207 is entrained in the insufflation gas, and themixture 209 is delivered through the trocar 201. The system may comprisevarious quick release couplings to facilitate removal of the aerosolgenerator 200 after completion of the aerosol delivery. For decoupling,the valve 254 is closed and the valves 255, 256 are opened to facilitatedirect flow of insufflation gas to the trocar inlet port 203. On releaseof the coupling, the aerosol generator 200 can be removed, allowing thecontinuing function of the trocar 201, for example for vison/camerasystems. In this version the aerosol delivery tube comprises an entryport for receiving a flow of insufflation gas. In this case theapparatus comprises flow diverting means for delivery of insufflationgas to the insufflation gas entry port of the trocar 203 and/or to theinsufflation gas entry port 252 of the aerosol delivery tube 206. Thissystem conveys the CO2 gas and thus entrains the aerosol with improvedflow rate to the distal end of the trocar.

As illustrated in FIGS. 14 to 17, another exemplary embodiment againcomprises an aerosol generator 200 and a trocar 201. Parts similar tothose described in other embodiments are assigned the same referencenumerals. In this case insufflation gas is directed along a pathwaycomprising a first upwardly directed leg 270 to the aerosol generator205 at which the generated aerosol is entrained in the insufflation gasand the mixture 209 is delivered along a downwardly directed leg 271 tothe trocar 201. There is a seal 275 to the trocar body to ensure thatthe insufflation gas passes up through the leg 271. The seal 275 may bea tapered seal as illustrated in FIGS. 14 and 15. Alternatively, a seal276 (FIG. 16) of an elastometric material may be used. The seal 276 iscompliant and may be used to achieve sealing with a range of tubes withdifferent diameters. The leg 271 may have additional parts, to aidbalanced flow. In this case the aerosol delivery tube means comprises aninner tube and an outer tube which are spaced-apart to define aninsufflation gas flow path therebetween. In this case there is a distalseal 275 between the outer tube and the trocar. The apparatus comprisesan aerosol delivery chamber and the insufflation gas flow path extendsinto the aerosol delivery chamber for entraining insufflation gas withthe aerosol, the insufflation gas with entrained aerosol being deliveredthrough the inner tube and extending from the inner tube into the trocarat the distal end of the tube means. In this case the distal end of theouter tube is located proximally with respect to the distal end of theinner tube to define an entry port 301 for insufflation gas.

This embodiment has an auxiliary seal and has bi-directional, co-axialfluid paths which has the advantage of eliminating the need for theadditional CO2 feed line of the embodiment of FIG. 12. This eliminatesadditional operational steps for clinicians. It also has the advantagesthat it works with existing set up and devices. It entrains the aerosolcloser to the delivery at the aperture plate and this improves aerosoldelivery and efficiency to the patient. The aerosol delivery is morecontrollable using this system.

Referring now to FIGS. 18 to 20 there is illustrated another aerosolgenerator system 200 and associated trocar 201. Parts similar to thosedescribed in other embodiments are assigned the same reference numerals.In this case an aerosol generator vibrating plate/mesh 280 is located atthe distal end of the trocar for localized generation of aerosol in oradjacent to a patient such as the abdomen 281. There is a proximalreservoir 282 for fluid to be aerosolized which is delivered to thegenerator 280 along a feed tube 283. The aerosol generator 280 isoperated/controlled by delivering signals along a lead 284 which extendsfrom a proximal connection part 285 to the aerosol generator 280. Inuse, insufflation gas passes through the trocar as illustrated andaerosol is entranced in the insufflation gas at the distal end of thetrocar 201. In this case the aerosol generator is located at a distalend of the trocar. The apparatus comprises first delivery means fordelivering insufflation gas to a location adjacent to the aerosolgenerator 280. The apparatus also comprises second delivery means fordelivery of liquid to be aerosolized to the aerosol generator 280. Thesecond delivery means in this case comprises a delivery tube extendingfrom a housing 282 for a liquid to the aerosol generator. In thisembodiment the aerosol generator is mounted to an outer tube whichextends through the trocar from the liquid housing. A distal end of theouter tube is located adjacent to a distal end of the trocar. Thissystem minimizes rain out and thus there is little or no medication lossbetween the aerosol generator and the patient.

The aerosol generator trocar insert may incorporate a closed cupconfiguration containing medication. This will facilitate theaerosolization of this drug only within the closed cup configuration andno other drug. Therefore the aerosolizing device can be used to target aparticular medical condition as dictated by the drug nebule that willmatch the aersolising device.

By positioning the aerosolizing device at the trocar the amount of thedrug deposited in the pneumoperitoneum, is greatly increased by as muchas two or three fold. This has the distinct advantage of aerosolizing areduced drug volume for the equivalent therapeutic value. In addition,less aerosolizing time will be required thus shortening surgicalprocedures.

In one arrangement a higher concentration variant of the drug may beaerosolized. This would allow for targeted delivery of small volumes ofhigh concentration drug to the aperture plate.

This has the distinct advantage of aerosolizing a smaller quantity of ahigher drug concentration which would have the equivalent therapeuticvalue of a larger quantity of standard drug concentration. In this way,the delivery time is substantially shortened. Therefore the aerosolizingdevice occupies less time in the trocar position, leading to shortersurgical procedures.

Larger particle size in the range of 5-10 microns may be aerosolized.This will further shorten delivery time and require the aersolisingdevice to occupy less time in the trocar position

These approaches enable the delivery of a complete dose and all foggingcleared during the insufflation phase in preparation for the start ofthe actual laparoscopic procedure.

Aerosol is generated directly at the trocar entry point to thepneumoperitoneum. This reduces rainout and loss of suspended aerosoldelivered to the pneumoperitoneum due to long tubing flow lengths,constrictions and changes in flow direction. The volume of medicationthat is delivered as suspended aerosol to the pneumoperitoneum isincreased for any given time.

Aerosol can be generated and delivered to the pneumoperitoneumcompletely independently of insufflator flow allowing more flexibilityin the timing of aerosol delivery during the procedure.

Access to the control mechanism for the aerosol generator is nearer tothe patient and accessible to the surgeon during the procedure. Thisreduces inconvenience and patient risk where the surgeon needs to makeimmediate changes in aerosol delivery during the course of a procedure.

Integration of the controller functionality into a single device removesthe cable link, as the product could be battery powered. Such cablescause inconvenience to the surgeon.

Designing the trocar nebulizer to receive a prefilled nebule of aparticular engagement geometry, ensures that no other drugs can be usedin an ‘off label’ manner.

The insertion of the nebule activates the vibration mesh thus creatingaerosolization, consequently pouring in a drug will not activate thevibration system to cause aerosolization.

In accordance with exemplary embodiments of the present invention, thereis increased treatment effectiveness and reduced treatment time throughincreased proportion of medication delivered as suspended aerosol.Aerosol delivery can be activated independently of insufflator gas flow.There is increased control and accessibility to the aerosol generatorfor surgeon at the patient site.

There is also reduced complexity of the device and risk of inconvenienceor obstruction for fully integrated aerosol generating device.

The aerosol generator trocar insert is compatible with a standard 10 mmtrocar by utilizing the camera or any other suitable port.

The aerosol generator trocar insert may be removed post deliveryallowing the surgeon to use to port as standard.

The aerosol generator trocar insert may be fully disposable, intendedfor single patient use.

The aerosol generator trocar insert may be a closed cup configurationcontaining appropriate medication quantity preventing excess medicationdelivery. There is a reduced risk of misuse of system through the use ofunapproved drugs.

Using a trocar to deliver an aerosol into a cavity during proceduresinvolving insufflation allows the concentrated local delivery of aerosolinto the cavity. The aerosol can be delivered quickly with optimisedflow rate, particle size and drug concentration. The dose delivered canbe maximized. The aerosol generator is only required to be in situ inthe trocar for a short time which means that the trocar can be used forother tools such as a camera during the procedure. By using an aerosolthe entire body cavity can be coated rather than a local area byinstillation. Because the aerosol generator is located at the trocaroptimum delivery of aerosol during insufflation pneumoperitoneum phasecan be achieved.

Referring to FIG. 34, there is illustrated another exemplaryinsufflation system in accordance with the present invention which issimilar to that described with reference to FIG. 1. In this case anaerosol jet nebulizer 300 is located in the insufflation line.

All of the trocar systems described above may be adapted to accommodatetwo or more aerosol generators. Such systems with more than one aerosolgenerator increase nebulizer output and reduce the time required todeliver a required amount of aerosol. One such system is illustrated inFIGS. 35 and 36. In this case an insufflation insert 500 for a trocar501 has two separate aerosol generators 502, 503. The gas flowpath inthis case is similar to that described above with reference to FIGS. 14to 16. There may be any desired number of aerosol generators. Forexample, FIG. 37 illustrates a modified version in which there are fouraerosol generators 510, 511, 512, 513.

There may be a seal 505 between the distal end of the trocar insert 500and the wall of the trocar to prevent insufflation gas from passingbetween the outer wall of the insert and the inner wall of the trocar.In an exemplary case the seal comprises a bulbous region 505 at thedistal end of the insert which is an interference fit in the shaft ofthe trocar. Such an arrangement facilitates ease of insertion andremoval of the trocar insert whilst maintaining a seal when the insertis in place in the trocar.

Referring to FIG. 38 a trocar insert 520 may have a length which issufficient to create a seal between the trocar insert 520 and the innersurface of the trocar 501. Typically the length is between 30 mm and 65mm. By reducing the distance the distance to be traveled by the aerosolwithin the narrow trocar insert the quantity of aerosol exiting thetrocar is increased.

Referring also to FIGS. 39 and 39( a) an inner tube 526 of a trocarinsert may be extended to a position close to the underside of anaerosol generator 527. In this case there is a cut angle across the topof the inner tube which may, for example, be at about 5° so as tomaximize entrainment of the aerosol with the gas so as to minimizelosses in the inner tube from rainout due to wall contact. Thus, lossesof aerosol in the insert is reduced. This system has the benefit ofchanneling the flow of generated aerosol for delivery to a patient. Someor all of these features may be used with any length of trocar insert.For example, it may be used in association with a short insert. Manydifferent arrangements are possible such as those illustrated in FIGS.40 to 45. There may be a small gap 530 which may be tapered (FIG. 40), atapered interface 531 (FIG. 41), an interface with castellations 532(FIG. 42), a single gas slit 533 (FIG. 43), or dual offset slits 534(FIG. 44) to promote vortex formation as illustrated in FIG. 45.

Referring to FIG. 46 there is illustrated an example of an aerosolinsert 540 with a modified interface between a proximal end of an innertube 541 of the insert and an aerosol generator 542. In this case theinner tube 541 comes into contact with the aerosol generator 542 and theinner tube has an inlet 543 for insufflation gas which is spaced belowthe proximal end of the inner tube 541. This modifies the aerosol flowdynamics for improved aerosol delivery efficiency.

A liquid reservoir for the aerosol generator may be modified tofacilitate efficient nebulization through a wide range of angles oforientation such as would be encountered in use during laparoscopicsurgery. One example is illustrated in FIG. 47 in which a reservoir 550is tapered. The reservoir 550 may be fitted with a removable plug 552.The plug may, for example, be of silicon.

Referring to FIG. 48 a trocar insert 560 of the present invention havingan aerosol generator 561 may include a valve 562 such as a flap valve tofacilitate the insertion of an instrument such as a trocar blade orobdurator. As the instrument is inserted, the flap valve 562 moves overin the direction of the arrow X to protect the aerosol generator 561.When the instrument is not present the flap 562 returns to a restposition and assists in directing the flow of aerosol generated by theaerosol generator down the shaft of the trocar.

Modifications and additions can be made to the embodiments of thepresent invention described herein without deporting from the scope ofthe present invention. For example, while the embodiments describedherein refer to particular features, the present invention includesembodiments having different combinations of features. The presentinvention also includes embodiments that do not include all of thespecific features described. Moreover, the features of the particularexamples and embodiments may be used in any combination.

The present invention is not limited to the embodiments hereinbeforedescribed, with reference to the accompanying drawings, which may bevaried in construction and detail.

1. Apparatus for use in procedures involving insufflation, comprising:an aerosol generator for aerosolizing a fluid; a trocar for delivery ofthe aerosol, the trocar comprising a housing to which the aerosolgenerator is mounted, the trocar having a proximal entry part forinsufflation gas and a distal end through which aerosol is delivered;and an aerosol delivery tube extending from the aerosol generator intothe trocar housing, the aerosol delivery tube having an aerosol outletlocated distally with respect to the insufflation gas entry port of thetrocar.
 2. The apparatus of claim 1, wherein a proximal end of theaerosol delivery tube is located adjacent to the aerosol generator. 3.The apparatus of claim 2, wherein the apparatus is adapted to directinsufflation gas from the trocar insufflation gas entry port to theproximal end of the aerosol delivery tube for entraining the aerosol inthe insufflation gas and delivery of the insufflation gas and entrainedaerosol through the trocar.
 4. The apparatus of claim 3, wherein a gapis provided between the aerosol delivery tube and the aerosol generatorfor delivery of insufflation gas into the aerosol delivery tube at theproximal end of the aerosol delivery tube.
 5. The apparatus of claim 4,wherein the gap is defined by an angled cut at the proximal end of theaerosol delivery tube.
 6. The apparatus of claim 5, wherein the angledcut is less than 20°.
 7. The apparatus of claim 5, wherein the angledcut is less than 15°.
 8. The apparatus of claim 5, wherein the angledcut is less than 10°.
 9. The apparatus of claim 5, wherein the angle cutis approximately 5°.
 10. The apparatus of claim 3, comprising a proximalseal between the trocar and the aerosol delivery tube.
 11. The apparatusof claim 3, wherein the aerosol delivery tube comprises an inner tuberadially spaced apart from an outer tube to define an insufflation gasflow path between the inner tube and the outer tube.
 12. The apparatusof claim 11, further comprising a distal seal between the outer tube andthe trocar.
 13. The apparatus of claim 1, further comprising acontroller configured to control the operation of the aerosol generator.14. The apparatus of claim 13, wherein the controller is remote from thetrocar.
 15. The apparatus of claim 13, wherein the controller is mountedto the trocar.
 16. The apparatus of claim 13, wherein the controller ismountable to the trocar.
 17. The apparatus of claim 13, wherein thecontroller is releasably mounted to the trocar.
 18. The apparatus ofclaim 1, further comprising a control system including configured tocontrol the operation of the aerosol generator, the control systemcomprising a first controller local to the trocar and a secondcontroller remote from the trocar.
 19. The apparatus of claim 13,wherein the controller is configured to control the flow rate of thefluid to be aerosolized.
 20. The apparatus of claim 13, wherein thecontroller is configured to deliver different flow rates of aerosol atdifferent stages of a surgical procedure.
 21. The apparatus of claim 13,wherein the controller is set to deliver a pre-set amount of aerosolinto insufflation gas.
 22. The apparatus of claim 13, wherein thecontroller is configured to control operation of the aerosol generatorresponsive to the insufflation gas.